First of all. A caste validity certificate is issued by the government. Caste Validity Certificateis a certificate issued by the government based on your caste. It is issued by checking the background details of the person like the grand father, great grand father, bloodline and relatives about the caste.

You can contact the Office of Backward Classes on your district and they will give you the documents list needed for caste validity certificate. Best of Luck with that.